Bill Gates says his mentor was a 6-foot-7 'giant' of global health also named Bill

Gates has little choice in the matter, as he noted in a recent Gates Notes blog post. Foege is 6 feet 7 inches tall. He towers over pretty much anyone in his vicinity.

But Gates also looks up to Foege because he considers the doctor one of his greatest mentors. Foege helped Gates and his wife Melinda learn the ropes of the public health world when they were starting the Bill and Melinda Gates Foundation in 1999.

"His intelligence, leadership, and humility over the last six decades have proven invaluable in the fight against disease and poverty," Gates wrote. "In the field of global health, he is a giant."

In the 1970s, as director of the Centers for Disease Control and Prevention, Foege helped lead the effort to eradicate smallpox. He crafted a system known as "surveillance and containment," which involves vaccinating only the people who've been in contact with people with a virus, not the entire population. The strategy saved countless hours and dollars.

Dr. Foege receives the Medal of Freedom for his work in epidemiology from President Obama in 2012. Kevin Lamarque/Reuters Smallpox was eradicated in 1980, and its disappearance helped give the public health world confidence that the same outcome is possible with other diseases, such as polio, Gates explained. Foege also led the charge in the 1980s to raise immunization rates in the developing world.

In 2012, President Obama awarded Foege the nation's highest civilian honor, the Medal of Freedom, for his achievements in public health.

Gates hasn't written as much about Foege as he has about his good friend Warren Buffett. But when he does talk about his mentor, it's always from the perspective of a student admiring a teacher. In 2014, Gates wrote in another blog post that he considers Foege one of his heroes.

Prior to leaving Microsoft, Gates said he didn't know much about the infectious diseases that plagued the developing world. Problems loomed so large, it was hard to grasp how anyone could begin solving them.

"One of the most valuable contributions Bill made to our learning was giving us a reading list with 81 different books and reports on global health issues," Gates wrote. They ranged from historical non-fiction to academic texts. "All these books opened a new world for me, making Bill's passion for fighting poverty and disease a passion of my own."

Now that Foege has largely passed the torch to the Gateses, the couple is building on Foege's efforts to raise immunization rates and wipe out harmful diseases. But Gates also hopes younger scientists will be inspired by Foege's accomplishments and choose to enter the public health world.

"I look forward to seeing what the next generation of public health students will accomplish," Gates wrote, " by following in this giant's footsteps."